摘要
目前常用的光学诊断大部分局限于二维成像,而基于层析成像的三维重建方法受限于空间和时间分辨率,无法实现等离子体边界的三维实时重建。提出一种基于光学分层理论的光场反卷积算法,利用光场重聚焦特性,结合聚焦测距法和刃边法,建立了光场深度与现实深度的关系,计算出点扩散函数,实现了单相机零调焦情况下的等离子体边界重建。为验证所提方法的可行性,以火焰为成像对象进行实验,其结果表明所提方法能够去除火焰分层图像中的离焦模糊,复原分层图像的原始结构。
Objective Identifying and reconstructing fusion plasma boundaries accurately are important research areas in controlled thermonuclear fusion.The traditional electromagnetic measurement methods will inevitably suffer from the accuracy problem arising from neutron radiation and long-term drift.The traditional optical diagnostic methods are non-intrusive and reach a high level of spatial resolution.However,they are commonly limited to two-dimensional imaging.As the processes within the plasma flow are inherently three-dimensional,it is necessary to develop a three-dimensional method for plasma measurement.In order to capture the dynamic information of the plasma and avoid signal distortion,threedimensional imaging must be achieved at a high speed in parallel or sequential imaging of multiple planes.However,the existing three-dimensional reconstruction methods based on tomography technology are limited by spatial and temporal resolution,and multiple images have to be captured from various angles,or complex experimental setups are needed.All the above methods are not applicable to reconstructing the three-dimensional plasma boundaries in real time.The light field camera is an emerging image acquisition device,in which a microlens array is placed between the main lens and the sensor.With the light field camera,multi-angle information can be captured within a single exposure.Plasma flow is the typical semi-transparent and dispersive media.To date,some studies have used the light field deconvolution algorithm to reconstruct the plasma,but the algorithm requires a long computation time.To this end,we propose a light field deconvolution algorithm based on optical sectioning imaging,which has the advantages of simplicity and speed.We hope Methods The depth information and point spread function are the key parameters of the method in this paper.We obtain these two parameters through experiments.First of all,with the digital refocusing technology,we calculate the relationship between the light-field refocused parameters and r
作者
张恒
吕雪
李华
杭芹
Zhang Heng;Li Xue;Li Hua;Hang Qi(Chongqing Key Laboratory of Computational Intelligence,Chongqing University of Posts and Telecommunications,Chongqing 400065,China;College of Computer Science and Technology,Chongqing University of Posts and Telecommunications,Chongqing 400065,China;Hefei Institute of Physical Science,Chinese Academy of Sciences,Hefei 230031,Anhui,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2023年第7期119-130,共12页
Acta Optica Sinica
基金
国家自然科学基金(12005030)
磁约束聚变安徽省实验室开放基金(2021AMF01004)
重庆市自然科学基金(cstc2021jcyj-bsh0252)在渝本科高校与中国科学院所属院所合作项目(HZ2021008)。
关键词
机器视觉
聚变等离子体
三维重建
光场重聚焦
光学分层成像
迭代反卷积
machine vision
fusion plasma
three-dimensional reconstruction
light field refocus
optical sectioning imaging
iterative deconvolution
